Derrick



M. BURKE.

DERRICK.

APPLICATION' msn Nov. 1. 1920.

Patented Nov. 8, 1921.

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e Aso A of the lower portion of the derrick, showing e the manner inwhich the standard is con- MICHAEL BURKE, 0F MOUNT PLEASANT, IOWA.

DERRICK.

Y n Specification of Letters atent.

rai-eared Nov. s, 19721.

Application filed November 1, 1920. Serial No. 421,071.

To all whom t may concern Be it known that I, MICHAEL BURKE, a citizenof the United States, residing at Mount Pleasant, in the county of Henryand State of Iowa, have invented certain new and useful Improvements inDerricks; and I do declare the following to be a full, clear, and exactdescription of the invention, such as will enable others skilled in theart to which it appertains to make and use the same. j

This invention relates to improvements in derricks, and has particularreference to a device of this class which is especially, although notnecessarily, designed for hoisting hay and the like.

The `,Principal vobject of the invention is to provide a device of theabove mentioned type embodying a base, and a` standard rising Vfrom thisbase, this standard carrying a pivotally mounted boom and this boombeing elevated in a step-by-step manner by novel elevating mechanismwhich is manually operated and is such that it retains the boom .ineachhigher elevated position to which it ismoved.l

Another object of the invention is to provide a derrick embodying theabove construction together with means for elevating the boomindependent of the above referred 'to hoisting means, this elevatingmeans serving to disenga'ge. the boom from the hoisting Alever so thatthe boom may be easily and readily returned to its normal position.

'Other objects and advantages of the in` vention will V,be apparentduring'the course of the following description.

In the `accompanying drawings forming a part of this specification andin which like lnumeralsare employed to designate like parts throughoutthe same: l 'Figure 1v is a side elevation of a derrick constructed inaccordance with my invention. Y Y

Fig. 2 isan end elevation with the boom shown in section.

Fig. 3 is a sectional view taken on the planeof the line 3--3 of Fig. 1,looking in the direction of the arrows.

Figft isa detail view, partly in section,

. yof, the line `5 5 of Fig. 1.

Referring to the drawings, wherein the preferred embodiment of myinvention is clearly illustrated, it will be seen that the numeral 1designates a base, which may be of any suitable construction, while thenumeral 2 designates a standard which rises from this base and supportsthe novel boom andhoisting vmechanism to be hereinafter specificallydescribed. It is desirable to mount the standard for rotation on thebase so that the load may be connected to the boom at any suitable pointand conveniently carried to the desired place of deposit. The standardmay be rotatably connected to the base in any suitable way, such as forinstance, as shown in Fig. 4. By reference to this ligure, it will beseen that the base is provided with an aperture and the standard carriesa removable headed member which passes through and is rotatable in thisaperture. For the purpose of increasing the rigidity of the device, I.will employ a plurality of braces 11 which are connected at their lowerends to the base and at their upper ends to a collar 5 through which thestandard extends and in which it is rotatable.

As before intimated, my derrick includes a boom V6 which is connected tothe standard by means of a quickly detachable clamp 7 This boom in itspreferred form is provided on its underface with a plurality of closelyspaced shoulders between which are cam surfaces, this constructionconstituting a plurality of ratchet teeth 8. A hoisting lever 9 ispivoted at its lower end in the clamp 10 and this lever is provided atits upper end with a T-head 11 which is adapted to engage said teeth andelevate the boom in a step-by-step manner and retain it in each 'higherposition to which it has been moved when movement is imparted to it bymeans ofthe manually operated cable 12. This cable is connected to anextension 13 connected to the T-head 11 and passing through a slot inthe boom 6. An eye or pulley 14 is arranged on the standard and thecable is permitted to pass through it and downwardly to a point near thebase, where it is adapted to be wound around a cleat 15 or other similarretaining device. vious that with this construction, by pullingdownwardly on the rope or cable l2, movement will be imparted to thelever 9 and that ysince this lever is engageable with the teeth 8, itwill elevate the boom in a step-by-step manner and Will automaticallylock it in each higher position to which it has been moved, thusenabling a single person to very easily elevate the boom with theslightest possibleY exertion.

. 'While any other means may be employed for disengaging the boom fromthe hoisting lever, I prefer to make use of the extremely simple meansconsisting of a cable or rope 16, which is connected to the outer end ofthe boom, passes through the pulley 17 on the standard and passesdownwardly along the latter and is connected to one of the cleats 15. Inpractical use, a fork or block and tackle will be connected to the boomthrough the medium of the short cable 18. Furthermore,lin order toprevent the base from moving, it is provided at its corners with leyes19 through which stakes can be driven for the purpose of retaining itstationary.

In all probability, persons skilled in the art to which this inventionrelates will be enabled to obtain a clear understanding of the inventionfrom the foregoing description taken in connection with the'. drawings.However, it may be advisable to review the operation of the4 device verybriefly. It is as follows: The hay or other article to be ele- ,vatedand carried to a suitable place of deposit,is connected to the dependingcable 18 by a suitable release fork or the like and it is elevated in astep-by-step manner by simply pulling downward onthe cable 12. Suchpulling of this cable will impart movement to the hoisting lever 9 anddue to its engagement with the teeth 8, the boom will be elevated in theabove set forth manner and will be retained in each position to which ithas been moved by this lever. When the load has been raised to thedesired elevation, the standard may be rotated and the load dropped atthe suitable place of deposit. In order to'permit theboom to return toits normal position, it is only necessary to catch hold of the cable 16and pull it downwardly, which will cause the boom to be Velevated anddisengaged from the hoisting lever- 9, the latter automatically moving`to its 'normal position by reason of its own weight. Effectiveengagement of the hoisting lever with the teeth 8 is insured because ofthe fact that this lever carries an extension which passes through theslot in the boom. Thus, the lever is at all times inthe proper positionfor effective operation. Y Y i Y With a device of the constructiondescribed, it will be seen that a single person may conveniently hoisthay or any other article v and move it to the ydesired point of deposit.

Thus, unnecessary labor can be -dispensed wlth.l The operator need notbe placed nnder unnecessary strain in elevating thelOQQIIl,

because by exerting a rather hard pull on the cable 12he can graduallyelevate this boom andvit vwill be locked in each higher position towhich it has been moved. These, and other advantages and features of myderrick have, no doubt. become apparent to the reader. Y

Since probably the best results may be obtained with the constructionand arrangement shown and described, this construction and arrangementis taken as thepreferred embodiment of my invention. However, I wish itto be understood that various minor changes in the shape', size,andarrangement of parts maybe resorted to without departing from thespirit of the invention or the scope of the subjoined claims.

I claim: Y

1. In a derrick, a base, a standard rising therefrom, a gravity loweredboom pivotally mounted on said standard, a hoisting cable for elevatingsaid boom, and a separate and independent means for elevating the boomin step by step manner and holding it inthe various positions to whichit has been moved,

said'cable serving to disengage said boom from the means when desired torestore the boom to its normal position.

2. In a derrick, a base, a standard risingl therefrom, a gravity loweredboom pivotally `mounted on said standard, a hoisting cable for elevatingsaid boom, and av separate and independent manually hoisted and gravitylowered lever pivoted on said'standard and slidably engaged at its upperend with said boom for elevating the latter instep by step manner andholding it in the various'positions taken, the aforesaid cableVV servingto vdisengage the boom from the lever to permit the latter to resume itsnormal position.

3. In a derrick, a base, a standard rising therefrom, a boom pivoted onthe standard and provided with shoulders, a hoisting lever pivoted onsaid standard having a head at its upper end for successively engagingsaid shoulders and 'elevatingth'e boom in a ilo step-by-step manner andretaining it in each higher position to which it has been moved, andmeans for actuating said lever. f

4. The structure set forth in claim 3, together with additional andseparate means for elevating the boom and V disengaging it from saidhoisting lever, permitting vvthe boom to be lowered by gravity. Y ,Y

5. In a derrick, a base, a standard rising therefrorma boom pivotallymounted `on the standard' and providedfon its under face with spacedshoulders and' cam surfaces between said shoulders, ahoisting` leveralsokpivoted on the standard, being slidably connected with the boom at-,itsupper end and havinganV integral vhead Vat this-end .for engagingsaidshoulders and riding. onrsaid cam surfaces for moving `the boom upwardlyin a .step step manner, actuating means iso ving of the boom.

for said lever, and means for disengaging said boom from said head topermit lower- 6. In a derrick, a base, a standard rising therefrom, aboom pivotally mounted on this standard, being provided with a slot, andbeing also provided on its underfaoe with ratchet teeth, a hoistinglever also pivoted to the standard and having a head at its outer endfor cooperation with said teeth, being lo also provided with a portionextending through said slot, a pull-cable connected to said portion foractuating the lever, and another cable conneted to the boom fordisengaging it from the lever. l5

In testimony whereof I have hereunto set my hand.

MICHAEL BURKE.

